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When a female of the heavy-chested persuasion looses control of her chest support causing boob-flesh to smother everyone in a five mile radius, cause blindness, as well as spontaneous boners.
Can be used in conjunction with the term tit-ripple, which usually precedes a titalanche through the snapping of a bra strap.
"For gods sake don't cause a titalanche, it'll be like a rubber raft going off in the back seat of the car!!!"

by Jeff and Kerri April 24, 2007
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